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Describe the physiological effects of caffeine


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Caffeine is a stimulant which has both physical and psychological effects. Physiologically, it functions as a vasoconstrictor, which means it causes the blood vessels to constrict, leading to increased alertness and energy. Caffeine can also increase respiration rate, heart rate, and blood pressure when consumed in large doses. In addition, it is known to reduce fatigue, improve concentration, and enhance physical performance.